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perf: fix stack data leak
[~shefty/rdma-dev.git] / drivers / hid / usbhid / hiddev.c
1 /*
2  *  Copyright (c) 2001 Paul Stewart
3  *  Copyright (c) 2001 Vojtech Pavlik
4  *
5  *  HID char devices, giving access to raw HID device events.
6  *
7  */
8
9 /*
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23  *
24  * Should you need to contact me, the author, you can do so either by
25  * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>
26  */
27
28 #include <linux/poll.h>
29 #include <linux/slab.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/smp_lock.h>
33 #include <linux/input.h>
34 #include <linux/usb.h>
35 #include <linux/hid.h>
36 #include <linux/hiddev.h>
37 #include <linux/compat.h>
38 #include "usbhid.h"
39
40 #ifdef CONFIG_USB_DYNAMIC_MINORS
41 #define HIDDEV_MINOR_BASE       0
42 #define HIDDEV_MINORS           256
43 #else
44 #define HIDDEV_MINOR_BASE       96
45 #define HIDDEV_MINORS           16
46 #endif
47 #define HIDDEV_BUFFER_SIZE      64
48
49 struct hiddev {
50         int exist;
51         int open;
52         struct mutex existancelock;
53         wait_queue_head_t wait;
54         struct hid_device *hid;
55         struct list_head list;
56         spinlock_t list_lock;
57 };
58
59 struct hiddev_list {
60         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
61         int head;
62         int tail;
63         unsigned flags;
64         struct fasync_struct *fasync;
65         struct hiddev *hiddev;
66         struct list_head node;
67         struct mutex thread_lock;
68 };
69
70 static struct hiddev *hiddev_table[HIDDEV_MINORS];
71
72 /*
73  * Find a report, given the report's type and ID.  The ID can be specified
74  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
75  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
76  * given type which follows old_id.
77  */
78 static struct hid_report *
79 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
80 {
81         unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
82         unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
83         struct hid_report_enum *report_enum;
84         struct hid_report *report;
85         struct list_head *list;
86
87         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
88             rinfo->report_type > HID_REPORT_TYPE_MAX)
89                 return NULL;
90
91         report_enum = hid->report_enum +
92                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
93
94         switch (flags) {
95         case 0: /* Nothing to do -- report_id is already set correctly */
96                 break;
97
98         case HID_REPORT_ID_FIRST:
99                 if (list_empty(&report_enum->report_list))
100                         return NULL;
101
102                 list = report_enum->report_list.next;
103                 report = list_entry(list, struct hid_report, list);
104                 rinfo->report_id = report->id;
105                 break;
106
107         case HID_REPORT_ID_NEXT:
108                 report = report_enum->report_id_hash[rid];
109                 if (!report)
110                         return NULL;
111
112                 list = report->list.next;
113                 if (list == &report_enum->report_list)
114                         return NULL;
115
116                 report = list_entry(list, struct hid_report, list);
117                 rinfo->report_id = report->id;
118                 break;
119
120         default:
121                 return NULL;
122         }
123
124         return report_enum->report_id_hash[rinfo->report_id];
125 }
126
127 /*
128  * Perform an exhaustive search of the report table for a usage, given its
129  * type and usage id.
130  */
131 static struct hid_field *
132 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
133 {
134         int i, j;
135         struct hid_report *report;
136         struct hid_report_enum *report_enum;
137         struct hid_field *field;
138
139         if (uref->report_type < HID_REPORT_TYPE_MIN ||
140             uref->report_type > HID_REPORT_TYPE_MAX)
141                 return NULL;
142
143         report_enum = hid->report_enum +
144                 (uref->report_type - HID_REPORT_TYPE_MIN);
145
146         list_for_each_entry(report, &report_enum->report_list, list) {
147                 for (i = 0; i < report->maxfield; i++) {
148                         field = report->field[i];
149                         for (j = 0; j < field->maxusage; j++) {
150                                 if (field->usage[j].hid == uref->usage_code) {
151                                         uref->report_id = report->id;
152                                         uref->field_index = i;
153                                         uref->usage_index = j;
154                                         return field;
155                                 }
156                         }
157                 }
158         }
159
160         return NULL;
161 }
162
163 static void hiddev_send_event(struct hid_device *hid,
164                               struct hiddev_usage_ref *uref)
165 {
166         struct hiddev *hiddev = hid->hiddev;
167         struct hiddev_list *list;
168         unsigned long flags;
169
170         spin_lock_irqsave(&hiddev->list_lock, flags);
171         list_for_each_entry(list, &hiddev->list, node) {
172                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
173                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
174                         list->buffer[list->head] = *uref;
175                         list->head = (list->head + 1) &
176                                 (HIDDEV_BUFFER_SIZE - 1);
177                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
178                 }
179         }
180         spin_unlock_irqrestore(&hiddev->list_lock, flags);
181
182         wake_up_interruptible(&hiddev->wait);
183 }
184
185 /*
186  * This is where hid.c calls into hiddev to pass an event that occurred over
187  * the interrupt pipe
188  */
189 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
190                       struct hid_usage *usage, __s32 value)
191 {
192         unsigned type = field->report_type;
193         struct hiddev_usage_ref uref;
194
195         uref.report_type =
196           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
197           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
198            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
199         uref.report_id = field->report->id;
200         uref.field_index = field->index;
201         uref.usage_index = (usage - field->usage);
202         uref.usage_code = usage->hid;
203         uref.value = value;
204
205         hiddev_send_event(hid, &uref);
206 }
207 EXPORT_SYMBOL_GPL(hiddev_hid_event);
208
209 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
210 {
211         unsigned type = report->type;
212         struct hiddev_usage_ref uref;
213
214         memset(&uref, 0, sizeof(uref));
215         uref.report_type =
216           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
217           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
218            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
219         uref.report_id = report->id;
220         uref.field_index = HID_FIELD_INDEX_NONE;
221
222         hiddev_send_event(hid, &uref);
223 }
224
225 /*
226  * fasync file op
227  */
228 static int hiddev_fasync(int fd, struct file *file, int on)
229 {
230         struct hiddev_list *list = file->private_data;
231
232         return fasync_helper(fd, file, on, &list->fasync);
233 }
234
235
236 /*
237  * release file op
238  */
239 static int hiddev_release(struct inode * inode, struct file * file)
240 {
241         struct hiddev_list *list = file->private_data;
242         unsigned long flags;
243
244         spin_lock_irqsave(&list->hiddev->list_lock, flags);
245         list_del(&list->node);
246         spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
247
248         if (!--list->hiddev->open) {
249                 if (list->hiddev->exist) {
250                         usbhid_close(list->hiddev->hid);
251                         usbhid_put_power(list->hiddev->hid);
252                 } else {
253                         kfree(list->hiddev);
254                 }
255         }
256
257         kfree(list);
258
259         return 0;
260 }
261
262 /*
263  * open file op
264  */
265 static int hiddev_open(struct inode *inode, struct file *file)
266 {
267         struct hiddev_list *list;
268         int res;
269
270         int i = iminor(inode) - HIDDEV_MINOR_BASE;
271
272         if (i >= HIDDEV_MINORS || i < 0 || !hiddev_table[i])
273                 return -ENODEV;
274
275         if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
276                 return -ENOMEM;
277         mutex_init(&list->thread_lock);
278
279         list->hiddev = hiddev_table[i];
280
281
282         file->private_data = list;
283
284         /*
285          * no need for locking because the USB major number
286          * is shared which usbcore guards against disconnect
287          */
288         if (list->hiddev->exist) {
289                 if (!list->hiddev->open++) {
290                         res = usbhid_open(hiddev_table[i]->hid);
291                         if (res < 0) {
292                                 res = -EIO;
293                                 goto bail;
294                         }
295                 }
296         } else {
297                 res = -ENODEV;
298                 goto bail;
299         }
300
301         spin_lock_irq(&list->hiddev->list_lock);
302         list_add_tail(&list->node, &hiddev_table[i]->list);
303         spin_unlock_irq(&list->hiddev->list_lock);
304
305         if (!list->hiddev->open++)
306                 if (list->hiddev->exist) {
307                         struct hid_device *hid = hiddev_table[i]->hid;
308                         res = usbhid_get_power(hid);
309                         if (res < 0) {
310                                 res = -EIO;
311                                 goto bail;
312                         }
313                         usbhid_open(hid);
314                 }
315
316         return 0;
317 bail:
318         file->private_data = NULL;
319         kfree(list);
320         return res;
321 }
322
323 /*
324  * "write" file op
325  */
326 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
327 {
328         return -EINVAL;
329 }
330
331 /*
332  * "read" file op
333  */
334 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
335 {
336         DEFINE_WAIT(wait);
337         struct hiddev_list *list = file->private_data;
338         int event_size;
339         int retval;
340
341         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
342                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
343
344         if (count < event_size)
345                 return 0;
346
347         /* lock against other threads */
348         retval = mutex_lock_interruptible(&list->thread_lock);
349         if (retval)
350                 return -ERESTARTSYS;
351
352         while (retval == 0) {
353                 if (list->head == list->tail) {
354                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
355
356                         while (list->head == list->tail) {
357                                 if (file->f_flags & O_NONBLOCK) {
358                                         retval = -EAGAIN;
359                                         break;
360                                 }
361                                 if (signal_pending(current)) {
362                                         retval = -ERESTARTSYS;
363                                         break;
364                                 }
365                                 if (!list->hiddev->exist) {
366                                         retval = -EIO;
367                                         break;
368                                 }
369
370                                 /* let O_NONBLOCK tasks run */
371                                 mutex_unlock(&list->thread_lock);
372                                 schedule();
373                                 if (mutex_lock_interruptible(&list->thread_lock))
374                                         return -EINTR;
375                                 set_current_state(TASK_INTERRUPTIBLE);
376                         }
377                         finish_wait(&list->hiddev->wait, &wait);
378
379                 }
380
381                 if (retval) {
382                         mutex_unlock(&list->thread_lock);
383                         return retval;
384                 }
385
386
387                 while (list->head != list->tail &&
388                        retval + event_size <= count) {
389                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
390                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
391                                         struct hiddev_event event;
392
393                                         event.hid = list->buffer[list->tail].usage_code;
394                                         event.value = list->buffer[list->tail].value;
395                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
396                                                 mutex_unlock(&list->thread_lock);
397                                                 return -EFAULT;
398                                         }
399                                         retval += sizeof(struct hiddev_event);
400                                 }
401                         } else {
402                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
403                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
404
405                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
406                                                 mutex_unlock(&list->thread_lock);
407                                                 return -EFAULT;
408                                         }
409                                         retval += sizeof(struct hiddev_usage_ref);
410                                 }
411                         }
412                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
413                 }
414
415         }
416         mutex_unlock(&list->thread_lock);
417
418         return retval;
419 }
420
421 /*
422  * "poll" file op
423  * No kernel lock - fine
424  */
425 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
426 {
427         struct hiddev_list *list = file->private_data;
428
429         poll_wait(file, &list->hiddev->wait, wait);
430         if (list->head != list->tail)
431                 return POLLIN | POLLRDNORM;
432         if (!list->hiddev->exist)
433                 return POLLERR | POLLHUP;
434         return 0;
435 }
436
437 /*
438  * "ioctl" file op
439  */
440 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
441 {
442         struct hid_device *hid = hiddev->hid;
443         struct hiddev_report_info rinfo;
444         struct hiddev_usage_ref_multi *uref_multi = NULL;
445         struct hiddev_usage_ref *uref;
446         struct hid_report *report;
447         struct hid_field *field;
448         int i;
449
450         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
451         if (!uref_multi)
452                 return -ENOMEM;
453         lock_kernel();
454         uref = &uref_multi->uref;
455         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
456                 if (copy_from_user(uref_multi, user_arg,
457                                    sizeof(*uref_multi)))
458                         goto fault;
459         } else {
460                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
461                         goto fault;
462         }
463
464         switch (cmd) {
465         case HIDIOCGUCODE:
466                 rinfo.report_type = uref->report_type;
467                 rinfo.report_id = uref->report_id;
468                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
469                         goto inval;
470
471                 if (uref->field_index >= report->maxfield)
472                         goto inval;
473
474                 field = report->field[uref->field_index];
475                 if (uref->usage_index >= field->maxusage)
476                         goto inval;
477
478                 uref->usage_code = field->usage[uref->usage_index].hid;
479
480                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
481                         goto fault;
482
483                 goto goodreturn;
484
485         default:
486                 if (cmd != HIDIOCGUSAGE &&
487                     cmd != HIDIOCGUSAGES &&
488                     uref->report_type == HID_REPORT_TYPE_INPUT)
489                         goto inval;
490
491                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
492                         field = hiddev_lookup_usage(hid, uref);
493                         if (field == NULL)
494                                 goto inval;
495                 } else {
496                         rinfo.report_type = uref->report_type;
497                         rinfo.report_id = uref->report_id;
498                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
499                                 goto inval;
500
501                         if (uref->field_index >= report->maxfield)
502                                 goto inval;
503
504                         field = report->field[uref->field_index];
505
506                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
507                                 if (uref->usage_index >= field->maxusage)
508                                         goto inval;
509                         } else if (uref->usage_index >= field->report_count)
510                                 goto inval;
511
512                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
513                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
514                                   uref->usage_index + uref_multi->num_values > field->report_count))
515                                 goto inval;
516                         }
517
518                 switch (cmd) {
519                 case HIDIOCGUSAGE:
520                         uref->value = field->value[uref->usage_index];
521                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
522                                 goto fault;
523                         goto goodreturn;
524
525                 case HIDIOCSUSAGE:
526                         field->value[uref->usage_index] = uref->value;
527                         goto goodreturn;
528
529                 case HIDIOCGCOLLECTIONINDEX:
530                         kfree(uref_multi);
531                         return field->usage[uref->usage_index].collection_index;
532                 case HIDIOCGUSAGES:
533                         for (i = 0; i < uref_multi->num_values; i++)
534                                 uref_multi->values[i] =
535                                     field->value[uref->usage_index + i];
536                         if (copy_to_user(user_arg, uref_multi,
537                                          sizeof(*uref_multi)))
538                                 goto fault;
539                         goto goodreturn;
540                 case HIDIOCSUSAGES:
541                         for (i = 0; i < uref_multi->num_values; i++)
542                                 field->value[uref->usage_index + i] =
543                                     uref_multi->values[i];
544                         goto goodreturn;
545                 }
546
547 goodreturn:
548                 unlock_kernel();
549                 kfree(uref_multi);
550                 return 0;
551 fault:
552                 unlock_kernel();
553                 kfree(uref_multi);
554                 return -EFAULT;
555 inval:
556                 unlock_kernel();
557                 kfree(uref_multi);
558                 return -EINVAL;
559         }
560 }
561
562 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
563 {
564         struct hid_device *hid = hiddev->hid;
565         struct usb_device *dev = hid_to_usb_dev(hid);
566         int idx, len;
567         char *buf;
568
569         if (get_user(idx, (int __user *)user_arg))
570                 return -EFAULT;
571
572         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
573                 return -ENOMEM;
574
575         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
576                 kfree(buf);
577                 return -EINVAL;
578         }
579
580         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
581                 kfree(buf);
582                 return -EFAULT;
583         }
584
585         kfree(buf);
586
587         return len;
588 }
589
590 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
591 {
592         struct hiddev_list *list = file->private_data;
593         struct hiddev *hiddev = list->hiddev;
594         struct hid_device *hid = hiddev->hid;
595         struct usb_device *dev = hid_to_usb_dev(hid);
596         struct hiddev_collection_info cinfo;
597         struct hiddev_report_info rinfo;
598         struct hiddev_field_info finfo;
599         struct hiddev_devinfo dinfo;
600         struct hid_report *report;
601         struct hid_field *field;
602         struct usbhid_device *usbhid = hid->driver_data;
603         void __user *user_arg = (void __user *)arg;
604         int i, r;
605         
606         /* Called without BKL by compat methods so no BKL taken */
607
608         /* FIXME: Who or what stop this racing with a disconnect ?? */
609         if (!hiddev->exist)
610                 return -EIO;
611
612         switch (cmd) {
613
614         case HIDIOCGVERSION:
615                 return put_user(HID_VERSION, (int __user *)arg);
616
617         case HIDIOCAPPLICATION:
618                 if (arg < 0 || arg >= hid->maxapplication)
619                         return -EINVAL;
620
621                 for (i = 0; i < hid->maxcollection; i++)
622                         if (hid->collection[i].type ==
623                             HID_COLLECTION_APPLICATION && arg-- == 0)
624                                 break;
625
626                 if (i == hid->maxcollection)
627                         return -EINVAL;
628
629                 return hid->collection[i].usage;
630
631         case HIDIOCGDEVINFO:
632                 dinfo.bustype = BUS_USB;
633                 dinfo.busnum = dev->bus->busnum;
634                 dinfo.devnum = dev->devnum;
635                 dinfo.ifnum = usbhid->ifnum;
636                 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
637                 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
638                 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
639                 dinfo.num_applications = hid->maxapplication;
640                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
641                         return -EFAULT;
642
643                 return 0;
644
645         case HIDIOCGFLAG:
646                 if (put_user(list->flags, (int __user *)arg))
647                         return -EFAULT;
648
649                 return 0;
650
651         case HIDIOCSFLAG:
652                 {
653                         int newflags;
654                         if (get_user(newflags, (int __user *)arg))
655                                 return -EFAULT;
656
657                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
658                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
659                              (newflags & HIDDEV_FLAG_UREF) == 0))
660                                 return -EINVAL;
661
662                         list->flags = newflags;
663
664                         return 0;
665                 }
666
667         case HIDIOCGSTRING:
668                 mutex_lock(&hiddev->existancelock);
669                 if (hiddev->exist)
670                         r = hiddev_ioctl_string(hiddev, cmd, user_arg);
671                 else
672                         r = -ENODEV;
673                 mutex_unlock(&hiddev->existancelock);
674                 return r;
675
676         case HIDIOCINITREPORT:
677                 mutex_lock(&hiddev->existancelock);
678                 if (!hiddev->exist) {
679                         mutex_unlock(&hiddev->existancelock);
680                         return -ENODEV;
681                 }
682                 usbhid_init_reports(hid);
683                 mutex_unlock(&hiddev->existancelock);
684
685                 return 0;
686
687         case HIDIOCGREPORT:
688                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
689                         return -EFAULT;
690
691                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
692                         return -EINVAL;
693
694                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
695                         return -EINVAL;
696
697                 mutex_lock(&hiddev->existancelock);
698                 if (hiddev->exist) {
699                         usbhid_submit_report(hid, report, USB_DIR_IN);
700                         usbhid_wait_io(hid);
701                 }
702                 mutex_unlock(&hiddev->existancelock);
703
704                 return 0;
705
706         case HIDIOCSREPORT:
707                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
708                         return -EFAULT;
709
710                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
711                         return -EINVAL;
712
713                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
714                         return -EINVAL;
715
716                 mutex_lock(&hiddev->existancelock);
717                 if (hiddev->exist) {
718                         usbhid_submit_report(hid, report, USB_DIR_OUT);
719                         usbhid_wait_io(hid);
720                 }
721                 mutex_unlock(&hiddev->existancelock);
722
723                 return 0;
724
725         case HIDIOCGREPORTINFO:
726                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
727                         return -EFAULT;
728
729                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
730                         return -EINVAL;
731
732                 rinfo.num_fields = report->maxfield;
733
734                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
735                         return -EFAULT;
736
737                 return 0;
738
739         case HIDIOCGFIELDINFO:
740                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
741                         return -EFAULT;
742                 rinfo.report_type = finfo.report_type;
743                 rinfo.report_id = finfo.report_id;
744                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
745                         return -EINVAL;
746
747                 if (finfo.field_index >= report->maxfield)
748                         return -EINVAL;
749
750                 field = report->field[finfo.field_index];
751                 memset(&finfo, 0, sizeof(finfo));
752                 finfo.report_type = rinfo.report_type;
753                 finfo.report_id = rinfo.report_id;
754                 finfo.field_index = field->report_count - 1;
755                 finfo.maxusage = field->maxusage;
756                 finfo.flags = field->flags;
757                 finfo.physical = field->physical;
758                 finfo.logical = field->logical;
759                 finfo.application = field->application;
760                 finfo.logical_minimum = field->logical_minimum;
761                 finfo.logical_maximum = field->logical_maximum;
762                 finfo.physical_minimum = field->physical_minimum;
763                 finfo.physical_maximum = field->physical_maximum;
764                 finfo.unit_exponent = field->unit_exponent;
765                 finfo.unit = field->unit;
766
767                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
768                         return -EFAULT;
769
770                 return 0;
771
772         case HIDIOCGUCODE:
773                 /* fall through */
774         case HIDIOCGUSAGE:
775         case HIDIOCSUSAGE:
776         case HIDIOCGUSAGES:
777         case HIDIOCSUSAGES:
778         case HIDIOCGCOLLECTIONINDEX:
779                 mutex_lock(&hiddev->existancelock);
780                 if (hiddev->exist)
781                         r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
782                 else
783                         r = -ENODEV;
784                 mutex_unlock(&hiddev->existancelock);
785                 return r;
786
787         case HIDIOCGCOLLECTIONINFO:
788                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
789                         return -EFAULT;
790
791                 if (cinfo.index >= hid->maxcollection)
792                         return -EINVAL;
793
794                 cinfo.type = hid->collection[cinfo.index].type;
795                 cinfo.usage = hid->collection[cinfo.index].usage;
796                 cinfo.level = hid->collection[cinfo.index].level;
797
798                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
799                         return -EFAULT;
800                 return 0;
801
802         default:
803
804                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
805                         return -EINVAL;
806
807                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
808                         int len;
809                         if (!hid->name)
810                                 return 0;
811                         len = strlen(hid->name) + 1;
812                         if (len > _IOC_SIZE(cmd))
813                                  len = _IOC_SIZE(cmd);
814                         return copy_to_user(user_arg, hid->name, len) ?
815                                 -EFAULT : len;
816                 }
817
818                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
819                         int len;
820                         if (!hid->phys)
821                                 return 0;
822                         len = strlen(hid->phys) + 1;
823                         if (len > _IOC_SIZE(cmd))
824                                 len = _IOC_SIZE(cmd);
825                         return copy_to_user(user_arg, hid->phys, len) ?
826                                 -EFAULT : len;
827                 }
828         }
829         return -EINVAL;
830 }
831
832 #ifdef CONFIG_COMPAT
833 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
834 {
835         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
836 }
837 #endif
838
839 static const struct file_operations hiddev_fops = {
840         .owner =        THIS_MODULE,
841         .read =         hiddev_read,
842         .write =        hiddev_write,
843         .poll =         hiddev_poll,
844         .open =         hiddev_open,
845         .release =      hiddev_release,
846         .unlocked_ioctl =       hiddev_ioctl,
847         .fasync =       hiddev_fasync,
848 #ifdef CONFIG_COMPAT
849         .compat_ioctl   = hiddev_compat_ioctl,
850 #endif
851 };
852
853 static char *hiddev_nodename(struct device *dev)
854 {
855         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
856 }
857
858 static struct usb_class_driver hiddev_class = {
859         .name =         "hiddev%d",
860         .nodename =     hiddev_nodename,
861         .fops =         &hiddev_fops,
862         .minor_base =   HIDDEV_MINOR_BASE,
863 };
864
865 /*
866  * This is where hid.c calls us to connect a hid device to the hiddev driver
867  */
868 int hiddev_connect(struct hid_device *hid, unsigned int force)
869 {
870         struct hiddev *hiddev;
871         struct usbhid_device *usbhid = hid->driver_data;
872         int retval;
873
874         if (!force) {
875                 unsigned int i;
876                 for (i = 0; i < hid->maxcollection; i++)
877                         if (hid->collection[i].type ==
878                             HID_COLLECTION_APPLICATION &&
879                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
880                                 break;
881
882                 if (i == hid->maxcollection)
883                         return -1;
884         }
885
886         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
887                 return -1;
888
889         init_waitqueue_head(&hiddev->wait);
890         INIT_LIST_HEAD(&hiddev->list);
891         spin_lock_init(&hiddev->list_lock);
892         mutex_init(&hiddev->existancelock);
893         hid->hiddev = hiddev;
894         hiddev->hid = hid;
895         hiddev->exist = 1;
896
897         /* when lock_kernel() usage is fixed in usb_open(),
898          * we could also fix it here */
899         lock_kernel();
900         retval = usb_register_dev(usbhid->intf, &hiddev_class);
901         if (retval) {
902                 err_hid("Not able to get a minor for this device.");
903                 hid->hiddev = NULL;
904                 unlock_kernel();
905                 kfree(hiddev);
906                 return -1;
907         } else {
908                 hid->minor = usbhid->intf->minor;
909                 hiddev_table[usbhid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
910         }
911         unlock_kernel();
912
913         return 0;
914 }
915
916 /*
917  * This is where hid.c calls us to disconnect a hiddev device from the
918  * corresponding hid device (usually because the usb device has disconnected)
919  */
920 static struct usb_class_driver hiddev_class;
921 void hiddev_disconnect(struct hid_device *hid)
922 {
923         struct hiddev *hiddev = hid->hiddev;
924         struct usbhid_device *usbhid = hid->driver_data;
925
926         mutex_lock(&hiddev->existancelock);
927         hiddev->exist = 0;
928         mutex_unlock(&hiddev->existancelock);
929
930         hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
931         usb_deregister_dev(usbhid->intf, &hiddev_class);
932
933         if (hiddev->open) {
934                 usbhid_close(hiddev->hid);
935                 wake_up_interruptible(&hiddev->wait);
936         } else {
937                 kfree(hiddev);
938         }
939 }
940
941 /* Currently this driver is a USB driver.  It's not a conventional one in
942  * the sense that it doesn't probe at the USB level.  Instead it waits to
943  * be connected by HID through the hiddev_connect / hiddev_disconnect
944  * routines.  The reason to register as a USB device is to gain part of the
945  * minor number space from the USB major.
946  *
947  * In theory, should the HID code be generalized to more than one physical
948  * medium (say, IEEE 1384), this driver will probably need to register its
949  * own major number, and in doing so, no longer need to register with USB.
950  * At that point the probe routine and hiddev_driver struct below will no
951  * longer be useful.
952  */
953
954
955 /* We never attach in this manner, and rely on HID to connect us.  This
956  * is why there is no disconnect routine defined in the usb_driver either.
957  */
958 static int hiddev_usbd_probe(struct usb_interface *intf,
959                              const struct usb_device_id *hiddev_info)
960 {
961         return -ENODEV;
962 }
963
964 static /* const */ struct usb_driver hiddev_driver = {
965         .name =         "hiddev",
966         .probe =        hiddev_usbd_probe,
967 };
968
969 int __init hiddev_init(void)
970 {
971         return usb_register(&hiddev_driver);
972 }
973
974 void hiddev_exit(void)
975 {
976         usb_deregister(&hiddev_driver);
977 }